The spread of Islam had a major role in the rise of several Indonesian kingdoms in these islands, such as the Sultanate of Banten, which was founded by King Hassanud-Deen in western Java, and Medang or Mataram Kingdom, which was founded by a military Shaivite king named Sri Sanjaya in East Java.
Thus, the island of Java became a great Islamic center, spreading the light of Islam among other islands.

There was also the Sultanate of Aceh in northern Sumatra, and the Kingdom of Demak in central Java, which was founded by Ramadhaan Faatimi in 832 A.H., as well as the kingdom of Palembang in South Sumatra.
Islam penetrated deep into the islands of Indonesia, moving from one island to the other safely and peacefully. In this part of the world, there is now the Republic of Indonesia, the largest Muslim country on earth.

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